From Flying Around the World in a Solar Powered Plane, one of 28 photos. Solar Impulse 2 flies over the Golden Gate Bridge in San Francisco at the end of its journey from Hawaii, part of its attempt to circumnavigate the globe, on April 23, 2016. (Noah Berger / AP)
All vehicles are free to operate in three dimensions i.e the longitudinal, vertical and horizontal axes.
In an aircraft, this movement are known by Pitch, Yaw and Roll.
Motion about the lateral axis
is called pitch and it’s a measure of how far an airplane’s nose is
tilted up or down.
This is controlled by the elevator.
Motion about the perpendicular axes is called yaw and
for aircraft it determines which way the nose is pointed
Aircraft do not necessarily fly in the same direction as the nose is
pointed if there are significant winds.)
This is controlled by the movement of the rudder
Motion about the
longitudinal axis is termed roll and in aircraft determines how much the
wings are banked.
This is controlled by the movement of the aileron.
In 1984 NASA Dryden Flight Research Center and the Federal Aviation
Administration (FAA) teamed-up in a unique flight experiment called the
Controlled Impact Demonstration (CID), to test the impact of a Boeing
720 aircraft using standard fuel with an additive designed to supress
fire. The additive FM-9, a high molecular-weight long chain polymer,
when blended with Jet-A fuel had demonstrated the capability to inhibit
ignition and flame propagation of the released fuel in simulated impact
Antimisting kerosene (AMK) cannot be introduced directly into a gas
turbine engine due to several possible problems such as clogging of
filters. The AMK must be restored to almost Jet-A before being
introduced into the engine for burning. This restoration is called
“degradation” and was accomplished on the B-720 using a device called a
“degrader”. Each of the four Pratt & Whitney JT3C-7 engines had a
“degrader” built and installed by General Electric (G.E) to break down
and return the AMK to near Jet-A quality.
In addition to the AMK research the NASA Langley Research
Center was involved in a structural loads measurement experiment which
included having instrumented dummies filling the seats in the passenger
compartment. Before the final flight on December 1, 1984, more then four
years of effort passed trying to set-up final impact conditions
considered survivable by the FAA. During those years while 14 flights
with crews were flown the following major efforts were underway: NASA
Dryden developed the remote piloting techniques necessary for the B-720
to fly as a drone aircraft; General Electric installed and tested four
degraders (one on each engine); and the FAA refined AMK (blending,
testing, and fueling a full size aircraft). The 14 flights had 9
takeoffs, 13 landings and around 69 approaches, to about 150 feet above
the prepared crash site, under remote control. These flight were used to
introduce AMK one step at a time into some of the fuel tanks and
engines while monitoring the performance of the engines. On the final flight
(No. 15) with no crew, all fuel tanks were filled with a total of
76,000 pounds of AMK and all engines ran from start-up to impact (the
flight time was 9 minutes) on the modified Jet-A.
The CID impact was spectacular with a large fireball
enveloping and burning the B-720 aircraft. From the standpoint of AMK
the test was a major set-back, but for NASA Langley, the data collected
on crashworthiness was deemed successful and just as important.
Bell X-22 experimental tilting ducted fan V/STOL (vertical and/or short take-off and landing) aircraft.
Takeoff was to selectively occur either with the propellers tilted vertically upwards, or on a short runway with the nacelles tilted forward at approximately 45°.
The program started in 1966, and was eventually cancelled in 1988, with only two units produced, the second being made after the first crashed.
Crew: two + six passengers Length: 39 ft 7 in (12.07 m) Wingspan: 39 ft 3 in (11.96 m) Wingspan (front wing): 22.916 ft (6.98 m) Height: 20 ft 8 in (6.31 m) Empty weight: 10,478 lb (4,753 kg) Max takeoff weight: 17,644 lb (8,003 kg) Powerplant: 4 × General Electric-YT58-GE-8D turboshaft engines, 1,267 hp (945 kW) each Propellers: three-bladed propellers mounted in wingtip swivelling ducts, 7 ft 0 in (2.13 m) diameter
Maximum speed: 221 kn (254 mph; 409 km/h) Service ceiling: 27,800 ft (8,500 m) Hover ceiling in ground effect : 12,000 ft (3,658 m) Hover ceiling out of ground effect : 6,000 ft (1,829 m)